Adhesive applying apparatus



Feb. 6, 1968 1 FOLEY ETAL 3,367,301

ADHES IVE APPLYING APPARATUS Filed March 2, 1965- 4 Sheets-Sheet 1 INVENTORS Harold J. Schlotter BY Thomas L. Foley Ronald E. Barry Attorney T. L. FOLEY ETAL ADHESIVE APPLYING APPARATUS Feb. 6, 1968 4 sheets-sheet 2 Filed March 2, 1965 INVENTORS Harold J Schlofler Thomas L Foley Ronald E. Barry Attorney Feb. 6, 1968 T. L. FOLEY ETAL ADHESIVE APPLYING APPARATUS 4 Sheets-Sheet 5 FI.G.4

INVENTO S Harold J. Schlofler Thomas L. Foley Ronald E. Barry Attorney FIG.7

T. L FOLEY ETAL ADHESIVE APPLYING APPARATUS fIZI Feb. 6, 1968 Filed March 2, 1965 INVENTORS Harold J. Schlofler Thomas L. Foley Ronald E. Barry Afiorhey United States Patent M 3,367,301 ADHESIVE APPLYING APPARATUS Thomas L. Foley and Harold J. Schlotter, Keokuk, Iowa,

assignors to Hoerner-Waldorf Corporation, a corporation of Delaware Filed Mar. 2, 1965, Ser. No. 436,495 7 Claims. (Cl. 118-3) ABSTRACT OF THE DISCLOSURE An apparatus for applying liquid adhesive to the closure flaps of both sides of a collapsed carton, the adhesive applicators being adjustable to accommodate various widths and lengths of cartons. Collapsed cartons are moved along a frame, adhesive applications apply a strip of adhesive along flap hinge lines, the applicators moving into and out of application position in timed adjustment. A limit switch stops carton movement after adhesive application until the carton to which adhesive has been applied is removed.

This invention relates to an apparatus and method for applying a liquid adhesive to the closure flaps of cartons and more particularly to an apparatus for automatically applying the liquid adhesive to the closure flaps on both sides of the carton while the carton is still in a collapsed condition.

In packaging articles into cartons at the manufacturing point, the packer has been burdened with the task of erecting the cartons and manually applying a liquid adhesive to the closure flaps on the bottom of the carton as the cartons are erected and then to the closure flaps on the top as the cartons are closed. This is necessary since the cartons are shipped in a collapsed condition for economy reasons and are erected as needed. The liquid adhesive is stored at the point of use and is applied with a brush or with a pressure-actuated device. Efforts to overcome the time lost in manually applying the liquid adhesive have been directed toward using self-sealing pressuresensitive adhesives that are applied to the closure flaps when the carton is manufactured. The pressure-sensitive adhesives have been used with limited success, due in part to the problems in handling and the limited amount of adhesive overlap on the closed flaps.

One of the primary objects of the present invention is to provide a liquid adhesive applying apparatus for uniformly applying adhesive to the closure flaps on both sides of a collapsed carton.

Another object of the present invention is to provide an apparatus for automatically applying liquid adhesive to the closure flaps on opposite sides of a collapsed carton.

Another object of the present invention is to provide an apparatus for applying a liquid adhesive to the closure flaps of collapsed cartons that is readily adjustable both in the length of the strip of adhesive applied as well as the distance between the strips of adhesive.

Another object of the present invention is to provide an apparatus for applying a liquid adhesive to the closure flaps of a collapsed carton which can be readily mounted in any convenient location on an assembly line.

Still another object of the present invention is to provide a liquid adhesive applying device for applying adhesive to the closure flaps of a collapsed carton that is fast in operation and requires a minimum amount of maintenance.

A further object of the present invention is to provide an apparatus for supplying collapse-d cartons having a liquid adhesive applied to the closure flaps on opposite sides of the carton to a supply point as needed.

Patented Feb. 6, 1968 A further object of the present invention is to provide a liquid adhesive applying apparatus for automatically supplying adhesively coated collapsed cartons to a supply point.

A further object of the present invention is to provide an apparatus which provides collapsed cartons having a liquid adhesive applied to the closure flaps on the carton to a supply point at a reduced cost per carton.

A still further object of the present invention is to provide an apparatus for supplying a collapsed carton having adhesive applied to its closure flaps to a sup ly point with the adhesive so located that the carton can be easily picked up from the apparatus.

These objects are accomplished by placing a stack of collapsed cartons within a carton hopper on an elongate frame which has a chain type conveyor mounted thereon for removing one carton at a time from the bottom of the hopper. Each collapsed carton is moved longitudinally along the frame in a continuous motion with the closure flaps extending outward to each side. In order to effectively seal the closure flaps on the top and bottom of the carton, an adhesive is applied to the surfaces of the shortest closure flap on the top and bottom of the carton. The adhesive is applied as a strip along the hinge line between the closure flap and the end wall of the carton. When the carton is erected, the shorter closure flaps will be folded inward first and the longer closure flaps folded into engagement with the shorter closure flaps. The adhesive will bond the inside facing of the longer closure flaps to the outside facing of the shorter closure flaps. This location for the adhesive assures a good bond for the corners of the longer closure flaps which is essential in this type of carton.

Adhesive is applied to these areas on the shorter closure flaps by pressure actuated adhesive applying devices that are moveable between operative and inoperative positions. A timing mechanism is synchronized with the motion of the conveyor to actuate the adhesive applying devices which are located above and below the closure flaps on the collapsed cartons. The timing mechanism controls both the time of actuation of the adhesive applying devices as well as the length of time that it is applied. The adhesive applying devices are adjustable simultaneously to vary the distance between the devices to correspond to the distance between the closure flaps. The motion of the carton is used to trip a limit switch at the end of the frame to stop the conveyor with the carton resting on the end of the frame. When the carton is removed, the limit switch will be released, starting the conveyor and repeating the cycle. The frame can be mounted at any convenient location with respect to a packing line so that the packer can remove the carton from the frame without leaving the packing point.

Other objects and advantages will become more readily apparent when the following detailed description is read in connection with the accompanying drawings, in which:

FIG. 1 is a top view of the adhesive applying apparatus.

-FIG. 2 is a side view of the adhesive applying apparatus.

FIG. 2A is a detail view of the actuating linkage for the adhesive applying guns.

FIG. 3 is a front view of the apparatus.

FIG. 4 is an enlarged view of the drive assembly for the conveyor and timing cams which control the operation of the apparatus.

FIG. 5 is a front elevation view of the drive assembly and timing cams.

FIG. 6 is an exploded view of one of the timing cams.

FIG. 7 is a schematic diagram of the pneumatic systern.

FIG. 8 is a wiring diagram showing the electrical systern.

Referring more specifically to the drawings, the liquid adhesive applying apparatus includes a main elongate tubular frame member 10 which can be suspended from the ceiling or supported on a base such as the tripod base 12 shown in FIG. 2. An idler sprocket 14 is mounted for free rotation on a shaft 16 located in opening 18 at the right hand end (FIG. 2) of the frame member. The shaft is adjustable in slots 19 on either side of the frame member and is held in position by nuts 17 mounted on the threaded ends of the shaft. A drive sprocket 20 is secured to drive shaft 22 in opening 24 at the other end of the frame and is journalled to rotate in bearings of conventional design. A continuous conveyor chain 26 is mounted on the sprockets to move from right to left (FIG. 2) across the top of the frame member and from left to right across the bottom of the frame member. Two carton pushers 28 are shown connected to the conveyor chain equidistant apart but any number can be equally spaced along the chain, depending on the length of the carton and the time required to operate the liquid applying apparatus.

The conveyor chain is driven by an electric motor 30 mounted on a motor frame 32 which is secured to frame member 10. A motor sprocket 34 is secured to shaft 35 which is coupled to the end of the motor shaft 36 and is connected to a driven sprocket 38 secured to the end of shaft 22 by a continuous drive chain 40. The conveyor chain is thereby driven directly by the motor. A small drive gear 42 (FIG. 4) is secured to the end of the motor shaft in a position to drive timing gears 44, 46 which are secured to timing shafts 45, 47 journalled in timer housing 48. It should be noted at this point that the timing gears 44, 46 both rotate counterclockwise and complete one revolution each time the conveyor chain moves through one-half of a revolution. As pointed out above, only two pushers are used on the conveyor chain but if three or more are used, the timing gears would have to be selected so that they make one revolution for each pusher on the conveyor chain. The timing shafts project outward from the timer housing and have timing cam assemblies 5 2, 54 mounted on the shafts so that they can be easily reached for adjustment. Knurled knobs 68 and 70 are threadedly mounted on the ends of shafts 45 and 47, respectively and are manually loosened to allow for adjustment of these assemblies, as more fully described hereinafter.

Adhesive is applied to the collapsed cartons as they are moved through an adhesive applying assembly 72 mounted on the main frame member. This assembly includes a lower cross member 74, an upper cross member 76 and a front cross member 78 which support end plates 80 and 82 in a parallel relation on each side of the main frame member. Adhesive is applied to the flaps of the collapsed carton by a set of upper adhesive applying guns 84 and a set of lower adhesive applying guns 86. Each of the guns is supplied with adhesive through tubes 85 which are connected to an adhesive supply tank 88. The tank is kept under pressure by an air supply line which is connected to an air supply source 91 through an air regulator 92. The flow of adhesive is controlled by pressure-actuated valves, which are well known in the art, located in the gun assemblies and the adhesive flows through a line of holes provided in each of the guns. The adhesive applying guns are more fully described in Patent No. 2,157,881. These guns can be purchased in different widths depending on the width desired and are interchangeable in the event the width of the strip is to be changed.

The guns are supported in the frame by upper gun mounts 96 and lower gun mounts 98. The upper gun mounts are mounted on an upper square control arm 100 and the lower gun mounts are mounted on a square lower control arm 101. Each of the assemblies is free to move longitudinally along the control arms but will rotate with the control arm when it is actuated. The distance between the upper gun assemblies is controlled by an upper traversing rod 102 and the distance between the lower gun assemblies by a lower traversing rod 104. These rods are reverse threaded at each end so that the gun assemblies on the upper control rod and the gun assemblies on the lower control rod move in equal but opposite directions. The traversing rods are interconnected by chain 106 which is mounted on sprockets 107, 108 so that both rods are turned simultaneously whenever an adjustment is to be made in the gun assemblies. A traversing rod crank 110 is provided on one end of the lower rod for making this adjustment. Since the collapsed cartons will be symmetrical with respect to the longitudinal axis of the frame member, all of the adhesive applying guns can be adjusted simultaneously.

The control rods are actuated by double acting pneumatic cylinders 1 12, 113 (FIG. 2a) having one end secured to brackets on end plate 82 and the other end secured to lever arms 114, 115 connected to the control rods 100 and 101, respectively. Referring to FIG. 7 a schematic diagram of the pneumatic system is shown. Air under a pressure of approximately 50 p.s.i. is admitted to the system from air pressure source 91 through air regulator 116. The air from the air regulator is directed through line 117 to electrically actuated air solenoid valves 118, 119 which control the air to the pneumatic cylinders. Each cylinder is double acting and is connected to the solenoid valve by air lines 120, 122 and 121, 123. When the cylinders are actuated to move the guns to an adhesive applying positiOn, suflicient travel is pro vided to assure that the guns will bear against the carton with, sufficient pressure to open the pressure-actuated valves in the guns, allowing the adhesive to flow onto the flap of the carton.

Collapsed cartons (shown dotted in FIG. 2) are stacked on the frame member with the shortest closure flaps on the top surface in the forward position. It should be understood that the short closure flap on the bottom surface of the collapsed carton is in the rearward position. The cartons are always stacked in the hopper in this position since the timing cam assemblies are adjusted according to the length of the long closure flap on the top surface and the length of the short closure flap on the bottom surface. The front portion of the closure flaps on each side of the carton rest on the lower horizontal ledges 126 on the box hoppers 128 and the rear edge of the carton is aligned with upright member 130. The box hoppers are free to move laterally on the upper cross member and are controlled in their motion by reverse threaded traversing rod 132 which is journalled into the end plates. Crank 134 is provided on the traversing rod to adjust the position of the box hoppers to conform to the width of a collapsed carton. The upright member is also adjustable longitudinally on the main frame member to correspond to the length of the collapsed carton.

A vertically adjustable plate 136 is mounted at the front of the stack of collapsed cartons to allow one carton at a time to be moved by the conveyor. The plate 136 has an upper horizontal ledge 138 and a lower pair of hold down springs 140. An adjustment screw 142 is threaded through the horizontal ledge and bears against the upper cross member. The plate can be moved up or down by merely turning the screw to vary the distance of the bottom of plate 136 from the top of frame 10. The hold down springs cooperate with hold down ledges 144 on the box hoppers to hold the carton down while the lower guns are in engagement with the bottom surface of the closure flaps on each side of the carton. If these are omitted, the guns will raise the carton off of the frame member without actuating the pressure-responsive adhesive valves.

When the upper guns are brought into engagement with the top surface of the flaps on a carton, the fiaps have a tendency to drop down without any adhesive being applied to the flaps. To correct this, a pair of roller bars 146 are mounted on transverse bar 148 and e ac u simultaneously with the upper guns to hold the carton flaps in position. Referring to FIG. 2A, lever arm 152 is secured to rod 148 and is connected to lever arm 114 by connecting rod 150. When the guns on rod 100 are brought into engagement with the flaps, connecting rod 150 will push against lever arm 152, turning rod 148 and bringing the roller bars 146 into engagement with the underside of the carton.

The adhesive applying assemblies are controlled by the timing cam assemblies, each of which includes two cam plates 52a, 52b and 54a, 54b. The cam assemblies act on cam rollers 56, 58 on microswitches 60 and 62 mounted on the timer housing, which control the operation of the solenoid valves 119 and 118, respectively.

Referring to FIG. 6 an exploded view of timing cam assembly 52 is shown. This cam assembly is used to control the lower gun assembly and its operation will be described for the lower gun assembly cycle. The cam assembly rotates in a counter clockwise direction (FIGS. 4 and 6) as previously indicated in the description of drive gears 44, 46. The back cam plate 52a has two cam surfaces 64a and 6411 on its outer periphery. Cam surface 64a extends around more than one-half of the cam periphery and is used to control the operative portion of the adhesive applying cycle. That is, when cam roller 56 drops from cam surface 64b to cam surface 64a, the lower adhesive applying assembly will be moved to an adhesive applying position and will remain in that position as long as the cam roller is positioned above this surface. The back cam plate is fixed on shaft 45 with the start 640 of cam surface 64b positioned to engage cam roller 56 when pusher 28 moves through the position shown in FIG. 1. Cam roller 56 will be pushed up, opening microswitch 60 and allowing the gun assembly to be moved to an inoperative position. This is the point where the largest collapsed carton would be picked up by the pusher. Front cam plate 52b is also provided with a cam surface 66b which corresponds in radius with cam surface 64b and a peripheral surface 66a which has a radius of curvature slightly less than the radius of cam surface 64a. The front cam plate is loosely mounted on shaft 45 with cam surface 66b forming a continuation of cam surface 64b. The fast drop cam surface 660 on plate 52b will determine the starting point for the lower gun assembly adhesive applying cycle. That is, cam roller 56 will drop from cam surface 66b to cam surface 66a at point 660, closing microswitch 60 and allowing the gun assembly to be moved to an operative position. The front cam is rotated to vary the peripheral length of the exposed portion of cam surface 64a which determines the amount of the cycle that the lower gun assemblies are in the operative position.

The front cam plate is adjusted with respect to the back cam plate by backing knurled knob 68 off of the threaded end of shaft 45. A graduated scale 70 is provided on the surface of plate 52a along the edge of cam surface 640 and is graduated in inches. A pointer 71 is provided on the surface of cam plate 52b on the edge of surface 66a. The graduated scale indicates the length of the shortest closure flap on the bottom surface of a collapsed carton. To set the cam assembly, the arrow is merely moved to the point on the scale which indicates this length. The drop off cam 660 will then be positioned at the point on the periphery of the cam assembly which corresponds to the point on the chain conveyor underlying the leading edge of the shortest closure flap on the collapsed carton. When this point on the chain passes the lower gun assemblies, they will be moved into engagement with the carton and remain in the operative position until point 640 is again brought into engagement with the cam roller 56. Since the guns are pressure actuated, it is not necessary to raise the gun assemblies until the next collapsed carton starts through the adhesive applying assembly.

Cam assembly 54 is used to control the upper gun assemblies but the operative and inoperative positions for the upper gun assemblies are just reversed. When cam surface 64b engages cam roller 58 on microswitch 62, the switch is closed, moving the gun assembly to the down position. When the cam point 660 moves past cam roller 58, the cam roller will drop, opening the microswitch and moving the upper gun assemblies to an inoperative position. The graduated scale on the back cam plate is also graduated in inches and the pointer is moved to the point on the scale, indicating the length of the longest closure flap on the top surface of the collapsed carton. The upper gun assemblies will then be moved to the inoperative position when the leading edge of the longest closure flap moves under the upper gun assemblies. The upper gun assemblies are moved to the operative position when the pusher starts across the top of the conveyor so that it will be in position to engage the leading edges of the short closure flaps as they move through the adhesive applying assembly. Since these guns are also pressure actuated, it is only necessary to raise the guns when the long closure flaps are moving under them.

In FIG. 8 a wiring diagram is shown for the electrical system. The electrical circuit includes a pair of supply lines L-1 and L2 which are connected to a suitable source of power, not shown. The microswitches 60 and 62 are connected across the line in series with the corresponding electrical solenoids 119 and 118, respectively, which actuate the four-way valves. Microswitch 60 is normally open and when switch contact 60a is closed with line contact 60b, solenoid 119 Will be actuated, moving the lower adhesive applying guns into contact with the under surface of the carton. Microswitch 62 is normally closed and when switch contact 62a is moved away from line contact 6212, the upper adhesive applying guns will be brought into contact with the upper surface of the carton.

The conveyor can run continuously as long as start switch 161 is left closed. However, this apparatus is designed to provide cartons as they are needed. A normally closed limit switch 160 has been mounted in slot 162 at the end of the main frame member and is connected across the line and in series with motor 30. When switch contact 164 is closed with line contact 166, the conveyor will run continually, moving cartons across the frame member. When a carton reaches the end of the frame member, it will engage switch actuator 170, opening the switch contact and stopping the motor. When the carton is removed, the switch contact will reclose, restarting the motor. A carton, therefore, will always be ready for use at the end of the frame member.

In operation, the hoppers are adjusted to the proper width and the upright member placed at the proper position for the length of the collapsed carton. A number of cartons are then stacked on the frame with the short closure flaps in the forward position. The short closure flaps on the bottom surface will be in the rearward position. Plate 136 is adjusted to the right height to allow one collapsed carton at a time to be moved from the stack by the conveyor by turning screw 142 to raise or lower the plate. Crank is then turned to set the proper distance between the upper and lower gun assemblies so that the adhesive applying guns overlie the closure flaps in close proximity to the hinge line.

Timing cams 54a and 54b are set so that the upper adhesive applying assemblies will apply a strip of glue to the forward or short closure flaps on the top surface of the cartons. Timing cams 52a and 52b are also set so that the lower gun assemblies apply adhesive to the rearward or short closure flaps on the bottom surface of the collapsed carton.

The air system is energized to pressurize the adhesive and the adhesive applying system. Switch contact 161 is closed to energize motor 30 and the bottom carton in the stack is moved to the end of the frame in one continuous motion and upon engaging switch actuator 170, switch contact Will be moved to the open position, stopping motor 30. As the carton moves through the adhesive applying assembly, the upper gun assemblies will be engaged by the carton to coat the forward closure flaps on the top surface of the carton. The upper gun assemblies are then moved to an inoperative position. As the carton moves along the conveyor, the lower gun assembly is moved to the operative position to coat the short closure flaps on the bottom surface of the assembly.

The end of the frame holding the carton is located in close proximity to the point of use so the user merely picks the adhesive coated carton off the frame and erects it. As the carton is removed, switch actuator 170 which is spring biased will snap back, closing switch contact 160 and restarting the cycle.

Although only a single embodiment of the present invention has been shown and described, it should be apparent that various changes and modifications can be made therein without departing from the scope of the appended claims.

What is claimed is:

1. An apparatus for applying a strip of adhesive to inner closure flaps of a tubular container comprising:

an elongated frame,

conveyor means mounted on said frame to move a said tubular container across said frame in substantially fiat, parallel relation of sides of said container to said frame whereby said container has an upper side and a lower side,

a pair of shafts in spaced vertical relation pivotally mounted transversely on said frame to the direction of travel of said conveyor means so that one of said shafts is above and the other said shaft is below a said container traveling across said frame,

a first adhesive applicator for applying adhesive to the outer surface of the lower inner closure flaps mounted on said one shaft,

a second adhesive applicator for applying adhesive to the outer surface of the lower inner closure flaps mounted on said other shaft,

timing means in timed relation to the movement of said conveyor means connected to said pair of shafts, said timing means controlling the length of adhesive applied by said first and second applicators to said inner closure flaps, and the sequence in which said first and second adhesive applicators apply adhesive,

positioning means operatively connected to said first and second adhesive applicators and to said timing means to move said applicators into and out of adhesive applying engagement with said upper and lower inner closure flaps as a said container is advanced across said frame,

hold down means engageable against the upper side of said container to hold said container against upward movement when adhesive is applied by said second adhesive applicator, and

roller means engageable against the lower side of said container to hold said container against downward movement when adhesive is applied by said first adhesive applicator.

2. The structure of claim 1 and in which said first and second adhesive applicators comprise pairs of glue applicators in spaced apart relation and means for adjusting the lateral distance between each pair of applicators.

3. The structure of claim 1 and in which said positioning means include first and second pressure actuated devices respectively connected to said first and second adhesive applicators on said pair of pivotally mounted shafts.

4. The structure of claim 3 and in which said timing means includes a first adjustable set of cams to control the first adhesive applicator, and a second adjustable set of cams to control the second adhesive applicator in movement toward or away from a said traveling container.

5. The structure of claim 1 and including a limit switch mounted on said frame engageable by a container after application of adhesive to upper and lower closure flaps whereby said drive means is stopped until said container is removed from the frame.

6. An apparatus for applying a strip of adhesive to inner closure flaps of a tubular container comprising:

an elongated frame,

conveyor means mounted on said frame to move a said tubular container across said frame in substantially fiat, parallel relation of sides of said container to said frame whereby said container has an upper side and a lower side,

a pair of shafts in spaced vertical relation pivotally mounted transversely on said frame to the direction of travel of said conveyor means so that one of said shafts is above and the other said shaft is below a said container traveling across said frame,

a first pair of adhesive applicators for applying adhesive to the outer surface of the lower inner closure flaps movably mounted on said one shaft,

a second pair of adhesive applicators for applying adhesive to the outer surface of the lower inner closure flaps movably mounted on said other shaft,

21 first set of adjustable cams,

a camshaft having a roller on one end engageable against said earns,

a second set of adjustable earns,

a camshaft having a roller on one end engageable against said second set of adjustable earns,

a pair of rotatable shafts connected to said first and second sets of cams respectively whereby said cams are rotated in relation to said conveyor means,

a pair of pressure actuated positioning devices operatively connected to each of said first and second pairs of adhesive applicators and to said other ends of said camshafts respectively to move said applicators into and out of adhesive applying engagement with said upper and lower inner closure flaps as a said container is advanced across said frame,

hold down means engageable against the upper side of said container to hold said container against upward movement when adhesive is applied by said second pair of adhesive applicators, and

roller means engageable against the lower side of said container to hold said container against downward movement when adhesive is applied by said first pair of adhesive applicators.

7. The structure of claim 6 and in which said pairs of adhesive applicators are laterally adjustable on their respective shafts.

References Cited UNITED STATES PATENTS 1,112,812 10/1914 Labombarde 118-225 1,119,289 12/1914 Labombarde 18225 1,957,470 5/1934 Milmoe 118247 2,157,881 5/1939 Andreasen l18149.8 2,571,204 10/1951 Conti 1l88 X 2,659,340 11/1953 Zinn 118239 X 3,052,210 9/1962 Hughes 1183 CHARLES A. WILLMUTH, Primary Examiner.

R. I. SMITH, Assistant Examiner. 

